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Nano-needle titania was fabricated from sol–gel reaction using titanium butoxide (TBO) as titania precursor and acetic acid (HAc). The wet gel after the sol–gel reaction was dried in supercritical carbon dioxide at 313 K and 10.4 MPa for the production of titania powder. The minor-axis of the nano-needles were measured by a scanning electron microscope and evaluated with respect to the effect of the initial molar ratios of HAc to TBO and reaction time in the sol–gel reaction process. A higher molar ratio of HAc in the sol–gel reaction results in a smaller minor axis of the nano-needle. The minor-axis of the titania nano-needle increases with increasing sol–gel reaction time. From these results, the minor-axis size of titania nano-needle could be controlled by the molar ratios of HAc to TBO and reaction time in the sol–gel reaction. The nano-needle titania was also applied to the fabrication of a thin film by a casting and solvent evaporation method. The surface roughness of the titania thin film from the nano-needle with various minor-axis was evaluated and compared with that from the nano-sphere titania. A smaller minor-axis of the nano-needle titania results in a larger roughness of the surface on the thin film. It is found that the roughness of the nano-needle film was larger than that using the nano-sphere. [ABSTRACT FROM AUTHOR]